TY - JOUR ID - 1372 TI - Effect of freeze-thaw cycle on strength and rock strength parameters (A Lushan sandstone case study) JO - Journal of Mining and Environment JA - JME LA - en SN - 2251-8592 AU - Hosseini, M. AU - Khodayari, A. R. AD - Department of Mining Engineering, College of Engineering, Imam Khomeini International University, Qazvin, Iran AD - Department of Mining and Metallurgical Engineering , Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran Y1 - 2019 PY - 2019 VL - 10 IS - 1 SP - 257 EP - 270 KW - Freeze-Thaw Cycle KW - Sandstone KW - Strength Parameters KW - Triaxial Compressive Strength DO - 10.22044/jme.2018.7619.1616 N2 - In an era of continued economic development around the globe, numerous rock-related projects including mining and gas/oil exploration are undertaken in regions with cold climates. Winters in the Iranian western and northwestern provinces are characterized by a high precipitation rate and a cold weather. Under such conditions, rocks are exposed to long freezing periods and several freeze-thaw (F-T) cycles. It is thus necessary to examine the impact of these cycles on the physical and mechanical properties of rocks. Considering the abundant sandstone resources in Iran, in this work, we focused on the Lushan sandstone by investigating the effects of F-T cycles and freezing temperatures on the uniaxial and triaxial compressive strengths, cohesion, internal friction angle, and elastic modulus of the rocks. To study the impact of the number of F-T cycles on the strength of rocks, the specimens frozen at -16 °C were subjected to 1, 4, 8, 16, and 32 F-T cycles. Similar tests were also carried out on the specimens frozen at -24 °C. Furthermore, a number of tests were undertaken at the ambient temperature (25 °C) on specimens that did not undergo an F-T cycle. According to the results obtained, an increase in the number of F-T cycles and freezing temperatures reduced the uniaxial and triaxial compressive strengths, cohesion, internal friction angle, and elastic modulus due to the growth of the existing cracks and the nucleation of new cracks in the rock. Consequently, the effective porosity increased, whereas the dry specific gravity decreased with more F-T cycles and lower freezing temperatures. UR - https://jme.shahroodut.ac.ir/article_1372.html L1 - https://jme.shahroodut.ac.ir/article_1372_b87ad09935f8dce967603b50f7665dde.pdf ER -